Wet tail is one of the most common and most deadly hamster illnesses. It is caused by the bacterium Lawsonia intracellularis, and is more accurately described as regional enteritis or proliferative ileitis. Wet tail is common in young, newly weaned hamsters. Stress, dietary changes, overcrowding and poor breeding contribute to wet tail. Sadly, there is no cure and most infected hamsters do not survive this disease.
There’s no sure way to prevent wet tail. The bacteria that cause this illness can be contracted even by hamsters who receive the best possible care. However, it is possible to significantly reduce your risk of purchasing a hamster that has or will have wet tail. First and most importantly, never buy a hamster from a pet store. I’ve personally observed the conditions under which hamsters are transported from their mill style breeders to chain pet stores. Even if the store itself provides good care, the crowding and unclean cages during transport as well as the stress of a store environment significantly increase the chance hamsters from pet stores will be infected with Lawsonia intracellularis. Some pet stores lose half or more of each hamster shipment to wet tail.
Choose a well-bred hamster from lines with no history of wet tail. Ask to inspect the breeder’s facilities and make sure that cages are kept fastidiously tidy. Wet tail is mostly transmitted by ingestion of infected fecal matter, so a dirty cage increases the risk of infection. Avoid breeders who use antibiotics on healthy hamsters to “prevent” wet tail–it doesn’t work and increases antibiotic resistance.
Once you’ve chosen your hamster, don’t make any sudden changes to its diet or routine. Don’t handle it for the first few days after bringing it home. Keep it in a dark room and open the cage only to offer food or water for at least three days. After three days you can begin gently stroking it, and after a week you can hold it and remove it gently from the cage.
Wet tail is treated with oral antibiotic therapy. Baytril (enroflaxin) is frequently used. Pedialyte or other pediatric electrolyte products may be offered in order to help the sick hamster stay hydrated. Subcutaneous fluids may be administered, as well as anti-diarrhea medicines. Unfortunately, even with the best of care, most infected hamsters will die. Some may linger or even appear to improve for several days before a sudden downturn. Others may pass within two days of the onset of symptoms. The rare wet tail survivor may always be intestinally fragile and should be treated with great care to avoid stress and foods that could provoke diarrhea.